1. Field of the Invention
The present invention relates to a modular jack and a modular jack connector which are suitable for use in twisted pair wiring system, and more specifically to a modular jack and a modular jack connector which suppress coupling in and out of a modular jack.
2. Prior Art
In a wiring system for information communication such as LAN (Local Area Network) or telephone, a modular jack which is used for branch and extension of a wiring is defined in U.S.A. Wiring System Standard TIA/EIA568 or Japanese Industrial Standards JISX5150.
In an office of recent years, installation of LAN has been being carried out actively, and TP (twisted pair wire) which is comparatively easy for laying and changing has been being used in many wiring systems in office. A wiring system using this TP and combining data system and telephone system is shown in FIG. 1.
In this wiring system, plurality of IDFs (Intermediate Distribution Panel) 62 which are concentrically wired to MDF (Main Distribution Frame) 61 are installed, for example, on every floor of building, one or more consent box 63 or boxes 63 which is or are wired to IDF 62 is or are provided to various place of floor, if necessary next step consent box 64 is connected to consent box 63, and terminal 65 is connected to each consent box 63, 64.
A modular connector type patch panel which concentrically wires TP is shown in FIG. 2, and consent box is shown in FIG. 3. As shown in these figures, plurality of modular connectors or modular jack connectors 71, 81 are arranged side-by-side to patch panel or consent box.
Modular jack is shown in FIG. 4. Modular jack 91 comprises housing 93 provided with opening 92 to which modular cable (not shown in the figure) is inserted, and eight conductor pins 94 which are incorporated within housing. Provided, this modular jack shown in the figure is according to an embodiment of the present invention, conventional modular jack is different from the figure in arrangement of conductor pins.
Modular jack connector is shown in FIG. 5. Modular jack connector 101 is constituted by mounting modular jack 91 on substrate 102 and mounting crimping terminal array 103 which is so-called 110 type on substrate 102. This modular jack connector 101 is according to an embodiment of the present invention, modular jack connector which combined modular jack and crimping terminal array has not been realized heretofore.
As shown in FIG. 6, crimping terminal 111 comprises blade portion 112 to which TP is inserted and lead portion 113 which is soldered to substrate 102.
Inner structure of conventional modular jack is shown in FIG. 7(a) and FIG. 7(b). As shown in FIG. 7(a), this modular jack 121 is provided with approximately cubic shaped hollow housing 122 of which left side end in the figure is opened, and inside of the housing 122, eight conductor pins 125 having convex bending portion 124 toward opening portion 123 (referred to as “forward”) are arranged at even intervals to right and left direction. Lower part of each conductor pin 125 corresponds to conductor pin leg 126 which passes through bottom of housing 122, and as shown in FIG. 7(b), numbers one to eight (1–8) are given to each conductor pin 125 in a manner of arranged order from right end as viewed opening portion 123 from outside. Each set of No. 1 and No. 2 conductor pins 125, No. 3 and No. 6 conductor pins 125, No. 4 and No. 5 conductor pins 125, and No. 7 and No. 8 conductor pins 125 is used as conductor pair. Conductor pair means a set of conductors connected to same twisted pair wires.
As shown in the figures, in conventional modular jack, all bending portions 124 of eight conductor pins 125 are lined up at same position toward forward, and eight conductor pin legs 126 are arranged in two lines, wherein No. 1, 3, 5, and 7 conductor pin legs 126 are in a forward line, and No. 2, 4, 6 and 8 conductor pin legs 126 are in a backward line.
In conventional U.S.A. Wiring System Standard, only category 5e which defines near end cross talk attenuation between twist pairs to be more than 43 dB at 100 MHz is provided. However, category 6 which defines up to frequency band of 250 MHz is engaged to be enacted in U.S.A. Wiring System Standard in 2002. In category 6, connector is required to have near end cross talk attenuation of more than 54 dB which exceeds category 5e 11 dB at 100 MHz and more than 46 dB at 250 MHz, it becomes necessary to cancel coupling (electromagnetic coupling) within modular jack and coupling caused by components (substrate, crimping terminal and etc.) other than modular jack. Coupling within modular jack is notably caused by arrangement of No. 3 and No. 6 conductor pins which are sandwiching No. 4 and No. 5 conductor pins, and moreover No. 3 and No. 6 conductor pair space being larger than other conductor pair space, this coupling originates deterioration of cross talk characteristics. Accordingly, improvement to reduce this coupling is desired.
As explained above, in order to fit for category 6 which defines near end cross talk attenuation to be more than 54 dB at 100 MHz and more than 46 dB at 250 MHz, it is necessary to suppress coupling in and out of modular jack. Also, the applicant is going to provide a component (modular jack connector) which combined and unified modular jack with twisted pair wire fitting terminal, it is necessary to suppress coupling in whole modular jack connector.